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Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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September 10, 1990 · Cessna 170A · N9157A

Elk Mountain, WY

Overview

Report Status
Probable Cause
Event Type
Accident
Date
September 10, 1990
Injury Outcomes
2 injuries (2 serious injuries)
Location
Elk Mountain, WY
Aircraft
Cessna 170A
Tail Number
N9157A
Operator
Lewis R Johnson
Injuries
Serious
Aircraft Damage
Substantial
NTSB Number
SEA90LA178

A WITNESS OBSERVED THE CESSNA 170A MAKE A LOW PASS OVER HIM. HE SAID IT STALLED AND ENTERED A NOSE-DOWN ATTITUDE WITH THE WINGS WAGGING. HE SAID THAT THE AIRPLANE HAD LEVELED JUST BEFORE IMPACT. THE AIRCRAFT WAS DESTROYED BY GROUND IMPACT AND THE TWO OCCUPANTS SUSTAINED SERIOUS INJURIES.

NTSB Probable Cause

THE PILOT'S FAILURE TO MAINTAIN FLYING SPEED WHILE AT AN ALTITUDE THAT DID NOT PROVIDE ADEQUATE TERRAIN CLEARANCE FOR A SAFE STALL RECOVERY.

Full Narrative

A WITNESS OBSERVED THE CESSNA 170A MAKE A LOW PASS OVER HIM. HE SAID IT STALLED AND ENTERED A NOSE-DOWN ATTITUDE WITH THE WINGS WAGGING. HE SAID THAT THE AIRPLANE HAD LEVELED JUST BEFORE IMPACT. THE AIRCRAFT WAS DESTROYED BY GROUND IMPACT AND THE TWO OCCUPANTS SUSTAINED SERIOUS INJURIES.

Flight

Event TypeAccident
Event Time08:10 MDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftCessna 170A
Tail NumberN9157A
Aircraft CategoryAir
DamageSubstantial
OperatorLewis R Johnson
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-360 · Reciprocating · 180
Seats4

People & Injuries

Injury Summary2 injuries (2 serious injuries)
Fatal0
Serious2
Minor0
Uninjured0
Total2
Crew 1Age 51 · Third Class

Conditions

ConditionsVMC
LightDaylight
WindCalm
Visibility60 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Observation Time14:15
Weather SourceWFAC

Appendix: Source Data